Description

A denial-of-service issue was addressed with improved input validation. This issue is fixed in iOS 27 and iPadOS 27. A remote attacker may be able to cause a denial-of-service.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.5",
  "pubDate": "2026-09-14T21:17:38.893Z",
  "pubdate": "2026-09-14T21:17:38.893Z",
  "executiveSummary": "A denial-of-service (DoS) vulnerability has been identified in iOS and iPadOS, stemming from insufficient input validation mechanisms. This security flaw enables a remote, unauthenticated attacker to disrupt the availability of the affected system by sending specifically crafted malicious input.\nThe vulnerability resides within the input processing logic of the operating system. By failing to adequately sanitize or validate incoming data streams, the system becomes susceptible to resource exhaustion or process termination when handling malformed packets or requests.\nThe primary impact of successful exploitation is the unexpected termination of system services or an overall system hang, effectively rendering the device unresponsive to user interaction or legitimate network traffic. This represents a significant risk to service availability and device stability.\nExploitation requires no specialized local access, as the vulnerability is accessible to remote attackers. As the flaw exists in the input validation layer, it likely necessitates the transmission of a payload designed to trigger an unhandled exception or critical error state within a system process. Users are strongly advised to update to iOS 27 or iPadOS 27 to address this security deficit.",
  "technicalDetails": "The vulnerability is characterized as an input validation failure, which, when triggered, leads to a denial-of-service condition. The root cause is an insecure implementation in the parsing or processing logic that handles incoming data. When the system receives data that deviates from expected formats or exceeds defined constraints, the lack of rigorous validation causes the handling process to enter an undefined or error-prone state.\nIn the context of iOS and iPadOS, this suggests that the vulnerable component is likely a low-level network daemon, system service, or a framework responsible for parsing external communication. The absence of sufficient bounds checking, type verification, or length validation allows an attacker to inject payloads that induce a buffer overflow, memory corruption, or a logic-based exception.\nThe attack flow begins with a remote actor identifying the targeted service or protocol listener exposed by the device. The attacker crafts a malicious input payload specifically engineered to bypass existing filters and hit the vulnerable code path. Upon reception of this packet or request, the targeted service attempts to process the payload without proper error handling or sanitization. This leads to a crash, infinite loop, or resource leak (such as CPU or memory exhaustion) depending on the nature of the validation failure.\nBecause the vulnerability is exploitable remotely, it does not require local authentication or elevated privileges prior to the initiation of the attack. The post-exploitation impact is limited to the denial of service, meaning the attacker forces the system or service into an unavailable state. This effectively prevents the device from performing its intended functions until a manual restart or service recovery occurs. The flaw affects versions prior to iOS 27 and iPadOS 27, where updated validation routines were implemented to discard or safely handle malformed input, thereby preventing the trigger of the crash condition. The remediation involves replacing the fragile parsing logic with more robust, sanitization-focused code that verifies all incoming data against strict schema and size limitations before it is permitted to reach the critical execution path."
}